Hydraulic shovel with arm incorporating breaker

ABSTRACT

A working machine of a hydraulic shovel which enables easy attaching and detaching of a chisel and affords smooth breaker work even in the vicinity of a wall, while enhancing chisel penetration and correspondingly improving the efficiency of the work. To this end, a bucket hinge pin (6d) is provided on one end of each of a pair of bucket brackets (6b) at a position offset from the axis of a breaker-incorporating arm (4b) toward the bucket cylinder (7), and, while the bucket (6) is in the tilted position, the chisel (10) is attached so as to extend through a space between the bucket hinge pin (6d) and the bucket link pin (8b) which is provided on the other ends of the bucket brackets (6b).

TECHNICAL FIELD

The present invention relates to a hydraulic power shovel with an armincorporating a breaker, capable of mounting both an excavating bucketand a breaker chisel.

BACKGROUND ART

Referring to FIG. 8, a conventional hydraulic shovel apparatus has amain structure 1, comprising a lower travelling structure la and anupper turret structure 1b, and is equipped with a working machine whichis swingably attached to the front side of the main structure 1 andwhich is composed of various parts such as boom 2, boom cylinder 3, arm4, arm cylinder 5, bucket 6, bucket cylinder 7, bucket link 8,intermediate link 9, and so forth. Hydraulic shovels, having thedescribed constructions, are widely used for various purposes includingexcavation.

In the meantime, currently known are hydraulic shovel working machinesof the type in which the arm 4 is replaced by a breaker-incorporatingarm which incorporates a breaker mechanism and which detachably carriesat its end a chisel for breaking operation (see, for example, JapaneseUtility Model Laid-Open No. 4119847). The operation for attaching thechisel to the working machine is as follows. The bucket cylinder 7 isoperated in the contracting direction so that the bucket 6 is movedforwardly, i.e., to a dumping position, through the action of the bucketlinks 8, the intermediate links 9, and the bucket brackets 6a, as shownin FIG. 9. A detachable chisel 10 is attached to the end of thebreaker-incorporating arm 4a in this state. According to thisarrangement, the apparatus becomes ready for performing breaker work,required in rock cutting or pavement breaking simply by attaching thechisel 10 in a short time. This eliminates laborious work whichotherwise may be required for detaching the bucket 6 from the workingmachine of the hydraulic shovel and mounting a breaker as an independentattachment, thus reducing the man-hours required in replacement work.

The above-described working machine of hydraulic shovel apparatus,however, suffers from a problem in that the breaking area is restricted,particularly when the breaking work has to be done in the vicinity of awall without demounting the bucket 6, because the chisel 10 can beattached only when the bucket 6 is in the dumping position. Morespecifically, referring to FIG. 10, when breaking work is conducted inthe vicinity of a wall W, the bucket cylinder 7 is contracted so as toset the bucket 6 to the dumping position while keeping the chisel 10 ina vertical posture, but a wide area is left without being broken,corresponding to the distance l₁ between the chisel 10 and the wall W.In addition, insufficient penetration depth is caused because thepenetration of the chisel 10 is limited to h1. This problem would beovercome by demounting the bucket 6. Such a solution, however, impairsthe working efficiency because the demounting of the bucket 6 isnecessary each time the breaking work is to be performed.

SUMMARY OF THE INVENTION

The present invention is aimed at obviating the above described problemof the known arts. Thus, an object of the present invention is toprovide a hydraulic shovel which is equipped with an arm incorporating abreaker and which permits easy attaching/detaching of a chisel withoutrequiring a bucket to be demounted from an arm, while achievingincreased chisel penetration and improved efficiency of work, such asbreaker work in the vicinity of a wall.

To this end, the present invention in its first aspect provides ahydraulic shovel with an arm incorporating a breaker, comprising: a boompivotally connected to a hydraulic shovel; the arm incorporating thebreaker and pivotally connected to an end of the boom; an arm cylinderpivotally connected between the arm incorporating the breaker and theboom; a bucket having a pair of bucket brackets fixed thereto, eachbucket bracket having one end pivotally connected to a bracket providedon an end of the arm incorporating the breaker; a pair of bucket linkseach having one end pivotally connected to one of the bucket bracketsand the other end pivotally connected to an intermediate link; theintermediate link having one end pivotally connected to the bracketprovided on the end of the arm incorporating the breaker and the otherend pivotally connected to the bucket link; and a bucket cylinder havingone end connected to the arm incorporating the breaker and the other endconnected to the intermediate link and the bucket links; wherein breakerwork is performed with a chisel which, while said bucket is in thetilted condition, is attached to the arm incorporating the breakerthrough the space defined between the pair of the bucket brackets andbetween the pair of bucket links at predetermined distances therefrom orattached to the same arm incorporating the breaker while said bucket isin the dumping condition.

An edge of the bucket between the pair of bucket brackets can beprovided with a notch which is spaced a predetermined distance from thechisel attached to the arm incorporating the breaker while the bucket isin the tilted condition.

According to a second aspect of the present invention, there is provideda hydraulic shovel with an arm incorporating a breaker, having a workingmachine which is mounted on a front portion of an upper turret structureand which includes a boom, an arm incorporating a breaker, and a bucket,wherein a bucket hinge pin is provided on the arm incorporating thebreaker with an offset from the axis of the arm incorporating thebreaker towards the bucket cylinder, and wherein breaker work isperformed with a chisel which, while said bucket is in the tiltedcondition, is attached to the arm incorporating the breaker through thespace defined between the pair of the bucket brackets and between thebucket hinge pin and the bucket link pin or attached to the same armincorporating the breaker while said bucket is in the dumping condition.The chisel may be attached, while said bucket is in a tilted condition,so as to extend through the space defined between the bucket hinge pinand the bucket link pin and between the pair of bucket brackets whichare spaced a predetermined distance from each other.

In the first and second aspects of the invention having the featuresstated above, when a breaker work has to be conducted, the bucketcylinder is extended so that the bucket, which is pivotally secured tothe end of the arm incorporating the breaker through a pair of brackets,is swung towards the tilted position by the action of the intermediatelink and the bucket links. As a result of this swinging motion, thebucket brackets move across the end of the arm incorporating thebreaker, so that the bucket is moved to one side of the armincorporating the breaker, whereby a space through which the chisel isto be mounted and attached is preserved between the bucket hinge pin andthe bucket link pin. In this state, the chisel can be mounted throughthe space between the pair of bucket links and attached to the armincorporating the breaker, thus enabling the hydraulic shovel to performbreaker work. Since the chisel is attached under such a condition thatthe bucket is in the tilted condition, breaker work in the vicinity of awall can be executed without causing interference between the wall andthe bucket, so that the chisel can approach the wall to perform breakingoperation in close proximity to the wall, thus achieving higher workefficiency. Furthermore, chisel penetration can be increased as comparedwith the conventional apparatuses, because the distance between thepavement surface and the bottom of the bucket or bucket bracket can beincreased by setting the bucket in the tilted position, whereby theworking machine can be adapted to a wider scope of work. It is possibleto attach the chisel to the arm incorporating the breaker also when thebucket is in the dumping position, so that the breaker work can beperformed with selection as necessary between the state in which thebucket is in the tilted condition and the state in which the bucket isin the dumping condition, thus facilitating clearing of the obstacle.The same advantages can be enjoyed also when the chisel is driventhrough the predetermined spacing between the pair of bucket brackets.When the breaker work is finished, the chisel is demounted from thebreaker-incorporating arm, so that the hydraulic shovel becomes readyfor ordinary excavating work. Notching at the bucket edge enables thelengths of the bucket bracket and bucket link to be reduced almost tothe same lengths as those in conventional apparatuses, so that theexcavating operation can be performed almost in the same sense ofoperation as that in conventional apparatuses.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are illustrations of a relevant portion of a firstembodiment of the hydraulic shovel working machine in a state in which abucket is tilted to allow attaching of a chisel, wherein FIG. 1A is aside elevational view, while FIG. 1B is a bottom plan view;

FIGS. 2A and 2B are a side elevational views of the relevant portion ofthe working machine, illustrative of the manner in which the chisel isdetached while the bucket is in the tilted position or the dumpingposition, respectively;

FIG. 3 is a view as viewed in the direction of the arrow Y in FIG. 2A;

FIGS. 4A, 4B and 4C are views as viewed in the direction of the arrow Zin FIG. 3, illustrative of the method for locking and unlocking thechisel, wherein FIG. 4A is an illustration of a tool, FIG. 4B is anillustration of the chisel in unlocked state, and FIG. 4C is anillustration of the chisel in locked state;

FIG. 5 is a sectional view corresponding to the A--A sectional plane ofFIG. 2A, with the chisel attached and locked;

FIG. 6A is a sectional view corresponding to the A--A sectional plane ofFIG. 2A, with the chisel detached;

FIG. 6B is a side elevational view of a dummy cap to be inserted into asleeve shown in FIG. 6A;

FIGS. 7A and 7B are illustrations of a relevant portion of a secondembodiment of the hydraulic shovel working machine in a state in which abucket is tilted to allow attaching of a chisel, wherein FIG. 7A is aside elevational view, while FIG. 7B is a bottom plan view;

FIG. 8 is a side elevational view of a conventional hydraulic shovelapparatus;

FIG. 9 is a side elevational view of a conventional hydraulic shovelapparatus with a chisel attached thereto; and

FIG. 10 is a side elevational view of a relevant portion of a workingmachine on the hydraulic shovel apparatus of FIG. 9 under breaker work.

THE BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the hydraulic shovel with an arm incorporatinga breaker in accordance with the present invention will be describedwith reference to the accompanying drawings.

Referring to FIGS. 1A and 1B, which show a first embodiment of thehydraulic shovel with an arm incorporating a breaker, numeral 4b denotesan arm incorporating a breaker, similar to that 4a shown in FIGS. 9 or10. The arm 4b has a front cap 4e to which a chisel 10 is attachable.The front cap 4e is provided at its end with a bracket 4g which isoffset from a chisel mounting bore 4h (see FIG. 6A). Bucket brackets 6b,6b, which are spaced from each other, are connected to the bracket 4gthrough bucket hinge pin 6d such that the bucket hinge pin 6d serves asa pivot for tilting or pivotal motion of the bucket 6. The bucketbrackets 6b, 6b, fixed to the bucket 6, are connected to a pair ofspaced parallel bucket links 8a, 8b through bucket link pin 8b which islocated adjacent the bucket 6.

The arrangement is such that the position of the bucket link pin 8b canbe shifted to the side of a later-mentioned chisel 10 opposite to thebucket hinge pin 6d, when the bucket 6 is swung toward a tilted positionabout the bucket hinge pin 6d while the chisel 10 is not attached to thearm 4b. Therefore, the chisel 10, in order that it is attached, can bemoved toward the front cap 4e of the arm 4b incorporating the breaker,through the space which is defined between the bucket hinge pin 6d andthe bucket link pin 8b and, as shown in FIG. 1B, between the bucketlinks 8a, 8a and between the bucket brackets 6b, 6b.

The bucket links 8a, 8a are connected through a bucket cylinder top pin7b to one end of an intermediate link 9a, the other end of which isconnected to the bracket 4g, and are connected also to an end of abucket cylinder rod 7a, so that the bucket 6 is actuated as a result ofthe operation of the bucket cylinder 7.

According to this arrangement, a change-over from ordinary excavatingoperation to a breaker work is accomplished as follows. The bucketcylinder 7 is extended to move the bucket 6 to the tilted position. As aresult of this operation, the bucket link pin 8b is shifted to aposition opposite to the bucket hinge pin 6d. After this shifting, thechisel 10 is attached to the front cap 4e through the space definedbetween the bucket link pin 8b and the bucket hinge pin 6d, the spacebeing formed between the pair of parallel bucket brackets 6b, 6b andbetween the parallel bucket links 8a, 8a. In this state, it is thuspossible to execute the breaker work without demounting the tiltedbucket 6, because the bucket 6 has been retracted to the tiltedposition.

It is assumed here that the breaker work is conducted at a position neara wall W, with the chisel 10 held in a vertical (up and down direction)position as shown in FIG. 1A. In this case, the distance l₂ between thechisel 10 and the wall W is much smaller than the distance l₁ (see FIG.10) in the known arts. At the same time, the heightwise distance h2between the lower end of the bucket 6 or the bucket link 8a and the roadsurface, such as a concrete-paved surface, is much greater than that h1(see FIG. 10) between the end of the bucket 6 and the ground surface inthe known arts, whereby the chisel penetration depth can be increased.When the breaking is required to reach a region in the close proximityof the wall W, the working machine is so controlled as to slightlyincline the breaker-incorporating arm 4b so that the breaker work can bedone with the chisel positioned as shown by phantom lines in FIG. 1A.These advantages enhance the efficiency of the breaker work conducted inthe area near a wall.

After completion of the breaker work, the chisel 10 is extracted fromthe front cap 4e of the arm 4b incorporating the breaker as shown inFIG. 2A, so that the hydraulic shovel becomes ready for excavating workas is the case of an ordinary hydraulic shovel.

A description will now be given as to the method of attaching anddetaching the chisel 10 to and from the arm 4b incorporating thebreaker. Referring first to the attaching method, the chisel 10 isinserted into a bore formed in the end of the arm 4b incorporating thebreaker, as shown in FIGS. 3, 4A and 4B. In this state, a pin portion12a of a tool 12 is inserted into a pin-receiving bore 11a of a lock pin11, and the tool 12 is rotated in the direction of the arrow A to theposition shown in FIG. 4C. The tool 12 is then withdrawn. In this state,as will be seen from FIG. 5, the outer surface of the lock pin 11contacts the surfaces of sleeves 4c, 4d provided in the front cap 4e ofthe arm 4b incorporating the breaker and the bottom of a recess 10aformed in the chisel 10, so that the chisel 10 is locked on the frontcap 4e of the arm 4b incorporating the breaker. The breaker work ispossible with this locked chisel.

In order to conduct ordinary excavating operation, the chisel 10 isdetached by a procedure reverse to that described above. Namely, thetool 12 is inserted into the pin-receiving bore 11a and is rotated inthe direction of the arrow B as shown in FIGS. 4C and 4B, whereby thechisel is unlocked. In this unlocked state, as shown in FIG. 6A, anotched surface 11b of the lock pin 11 faces inwardly, so that thechisel 10 can easily be detached from the front cap 4e of the arm 4bincorporating the breaker without difficulty. It is thus possible toattach and detach the chisel 10 quickly and easily. After the detachingof the chisel 10, a dummy cap 13, having a recess 13a as shown in FIG.6B, is inserted into the sleeves 4c, 4d and is locked in the same way asthat for the chisel 10, thereby preventing soil and sand from enteringthe chisel mounting bore 4h in the sleeves 4c, 4d.

A second embodiment of the hydraulic shovel with an arm incorporating abreaker of the present invention will be described with reference toFIGS. 7A and 7B. The basic construction of the second embodiment issimilar to that of the first embodiment, so that the followingdescription will focus only on the points which discriminate the secondembodiment. In this embodiment, an edge of the bucket 6 is notched as at6c over a region substantially corresponding to the spacing between thepair of brackets 6b. The notch 6c is intended to prevent interferencebetween the bucket 6 and the chisel 10 which otherwise may occur whenthe bucket 6 is held at the tilted position during attaching of thechisel 10 or during breaker work. The notch 6c enables the bucket 6 tobe mounted closer to the chisel 10 than in the first embodiment, so thatthe lengths of the bucket brackets 6b and the bucket links 8a can bereduced as compared with those in the first embodiment. Thus, the secondembodiment offers breaking performance equivalent to that of the firstembodiment and can perform excavating operations with the same sense ofcontrol as that for the conventional working machine.

Although the hydraulic shovel with an arm incorporating a breaker inaccordance with the invention has been described in detail, it is to beunderstood that the chisel can be attached while the bucket is in thedump position, as illustrated in FIG. 2B. Thus, the chisel can beattached either in a state in which the bucket is in the dumpingposition or in a state in which the bucket is in the tilted position,and one of these states can be selected as necessary so as to enable theworking machine to easily clear any obstacle.

INDUSTRIAL APPLICABILITY

The hydraulic shovel with an arm incorporating a breaker of the presentinvention enables easy attaching and detaching of a chisel, both whenthe bucket is in the tilted position and when the same is in the dumpposition. The working machine also enables breaker work to be conductedin the close proximity of a wall, while enhancing the chisel penetrationand, hence, breaker work efficiency.

What is claimed is:
 1. A hydraulic shovel with an arm incorporating abreaker, comprising:a boom pivotally connected to a hydraulic shovel;the arm incorporating the breaker and pivotally connected to an end ofsaid boom; an arm cylinder pivotally connected between said armincorporating the breaker and said boom; a bucket having a pair ofbucket brackets fixed thereto, each bucket bracket having one endpivotally connected to a bracket provided on an end of said armincorporating said breaker; a pair of bucket links each having one endpivotally connected to one of said bucket brackets and the other endpivotally connected to an intermediate link; the intermediate linkhaving one end pivotally connected to the bracket provided on the end ofsaid arm incorporating the breaker and the other end pivotally connectedto one of said bucket links; and a bucket cylinder having one endconnected to said arm incorporating the breaker and the other endconnected to said intermediate link and said bucket links; whereinbreaker work is performed with a chisel which, while said bucket is in atilted condition, is attachable to the arm incorporating the breakerthrough a space defined between the pair of the bucket brackets andbetween the pair of bucket links at predetermined distances therefrom,and, while said bucket is in a dumping condition, is attachable to thesame arm incorporating the breaker while said bucket is in the dumpingcondition.
 2. A hydraulic shovel with an arm incorporating a breakeraccording to claim 1, wherein an edge of said bucket between said pairof bucket brackets is provided with a notch which is spaced apredetermined distance from said chisel attached to said armincorporating the breaker while said bucket is in the tilted condition.3. A hydraulic shovel with an arm incorporating a breaker, having aworking machine which is mounted on a front portion of an upper turretstructure and which includes a boom, said arm incorporating a breaker, abucket, and a bucket cylinder, wherein a bucket hinge pin is provided onsaid arm incorporating the breaker with an offset from the axis of saidarm incorporating the breaker towards said bucket cylinder, and whereinbreaker work is performed with a chisel which, while said bucket is in atilted condition, is attachable to the arm incorporating the breakerthrough a space defined between the bucket hinge pin and a bucket linkpin, and, while said bucket is in a dumping condition, is attachable tothe same arm incorporating the breaker while said bucket is in thedumping condition.
 4. A hydraulic shovel with an arm incorporating abreaker according to claim 3, wherein the attaching of the chisel in thestate in which said bucket is in the tilted condition is conductedthrough a space defined between said bucket hinge pin and said bucketlink pin and between a pair of bucket brackets which are spaced apredetermined distance from each other.
 5. A hydraulic shovel with anarm incorporating a breaker, comprising:an arm (4b) incorporating abreaker main structure and including a chisel (10), only a base portionof said chisel (10) being received in said arm so as to be connected tosaid breaker main structure; a bucket (6) mounted on an end of said arm(4b); and a link mechanism including a bucket cylinder (7) for actuatingsaid bucket (6), an intermediate link (9a) and a bucket link (8a);characterized in:that a bracket (4g) is disposed at a lateral sideadjacent the end of said arm (4b) at an offset to one side from saidchisel (10); that a bucket hinge pin (6d) serving as a pivot for thepivotal motion of said bucket (6) is provided on said bracket (4g) at aposition deviating from the end of said arm (4b); that a bucket link pin(8b) interconnecting said bucket (6) and said bucket link (8a) islocated at a position on the rear side of said bucket (6) which, whensaid bucket (6) is rotated counterclockwise about said bucket hinge pin(6d), moves to a position on the side of said chisel (10) opposite tosaid bucket hinge pin (6d); that, by means of a link mechanism includingsaid intermediate link (9a) connected through a pin to said bracket (4g)and said bucket link (8a) connected through a pin to said intermediatelink (9a); and that said bucket link pin (8b) is located at a positionwhich is beyond said chisel (10) in the counterclockwise direction,whereby said chisel (10) can be inserted into the end of said arm (4b)through a space defined between said bucket hinge pin (6d) and saidbucket link pin (8b), thereby enabling said hydraulic shovel to performbreaker work.
 6. A hydraulic shovel with an arm incorporating a breakeraccording to claim 5, wherein said bucket hinge pin (6d) is disposed onsaid bracket (4g) laterally offset from the end of said arm (4b) andprojecting to one side of said chisel (10).
 7. A hydraulic shovelcomprising:a main structure including a lower traveling structure and anupper turret structure; a boom having a first end and a second end, saidfirst end of said boom being pivotally connected to said upper turretstructure; an arm incorporating a breaker mechanism; said arm having afirst end, a second end, and an axis; said first end of said arm beingpivotally connected to said boom at a location remote from said firstend of said boom; said second end of said arm being adapted todetachably receive a chisels, said chisel having a first end and asecond end; an arm cylinder having a first end and a second end, saidfirst end of said arm cylinder being pivotally connected to said boom,said second end of said arm cylinder being connected to said first endof said arm; an offset bracket connected to said second end of said armand extending outwardly from the axis of said arm; a bucket having arear face; a pair of spaced apart bucket brackets, each of said bucketbrackets having a first end and a second end, with the first end of eachof said bucket brackets being pivotally connected to said offsetbracket, and the second end of each of said bucket brackets beingsecured to said rear face of said bucket, the spacing between the spacedapart bucket brackets being greater than an outside diameter of saidchisel; an intermediate link having a first end and a second end, withsaid first end of said intermediate link being pivotally connected tosaid offset bracket; a pair of bucket links, each of said bucket linkshaving a first end and a second end, with the first end of each of saidbucket links being pivotally connected to a respective one of saidbucket brackets, and the second end of each of said bucket links beingpivotally connected to the second end of said intermediate link; and abucket cylinder having a first end and a second end, with the first endof said bucket cylinder being pivotally connected to said arm and thesecond end of said bucket cylinder being pivotally connected to saidsecond end of said intermediate link; said offset bracket being offsetfrom said axis of said arm toward said bucket cylinder so that thepivotal connection of the first end of each of said bucket brackets tosaid offset bracket is offset from said axis of said arm toward saidbucket cylinder whereby:when said bucket cylinder is contracted to movesaid bucket to a dumping position, said chisel can be attached to saidsecond end of said arm so that breaker work can be performed with theattached chisel without requiring said bucket to be demounted from saidarm; and when said bucket cylinder is extended to move said buckettoward said main structure in a tilted position, said chisel can bepositioned in a space between said bucket brackets and between saidbucket links without interference, and the thus positioned chisel can beattached to said second end of said arm so that breaker work can beperformed with the thus attached chisel without requiring said bucket tobe demounted from said arm.
 8. A hydraulic shovel in accordance withclaim 7, wherein said space is between said second end of said bucketcylinder and an edge of said bucket, said edge of said bucket extendingbetween the pair of bucket brackets and being provided with a notch toprevent interference between said bucket and the chisel which otherwisemight occur when said bucket is held at the tilted position duringattaching of the chisel to the arm or during breaker work.
 9. Ahydraulic shovel in accordance with claim 7, wherein the first end ofeach of said bucket brackets is pivotally connected to said offsetbracket by a bucket hinge pin, with the bucket hinge pin being offsetfrom the axis of said arm toward said bucket cylinder.
 10. A hydraulicshovel in accordance with claim 9, wherein the first end of each of saidbucket links is pivotally connected to a respective one of said bucketbrackets by a bucket link pin.
 11. A hydraulic shovel in accordance withclaim 10, wherein said space between said bucket brackets and betweensaid bucket links is also between the bucket hinge pin and the bucketlink pin.
 12. A hydraulic shovel in accordance with claim 11, whereinsaid second end of said arm comprises a front cap having said offsetbracket extending outwardly therefrom, wherein said front cap contains abore for receiving said first end of the chisel, and a locking mechanismfor locking the first end of the chisel within said bore.
 13. Ahydraulic shovel in accordance with claim 7, wherein said second end ofsaid arm comprises a front cap having said offset bracket extendingoutwardly therefrom, wherein said front cap contains a bore forreceiving said first end of the chisel, and a locking mechanism forlocking the first end of the chisel within said bore.
 14. A hydraulicshovel in accordance with claim 13, wherein said first end of saidchisel has a recess, and wherein said locking mechanism comprises arotatable pin having a first rotation position wherein said rotatablepin engages the recess in said chisel to lock said first end of saidchisel in said bore, and a second rotation position wherein saidrotatable pin does not engage the recess in said chisel, therebypermitting the chisel to be easily attached to and detached from saidfront cap.